postgresql/src/backend/utils/adt/not_in.c

140 lines
3.4 KiB
C

/*-------------------------------------------------------------------------
*
* not_in.c
* Executes the "not_in" operator for any data type
*
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/Attic/not_in.c,v 1.24 2000/07/07 21:12:50 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
*
* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
* X HACK WARNING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! X
* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*
* This code is the OLD not-in code that is HACKED
* into place until operators that can have arguments as
* columns are ******REALLY****** implemented!!!!!!!!!!!
*
*/
#include "postgres.h"
#include "access/heapam.h"
#include "utils/builtins.h"
static int my_varattno(Relation rd, char *a);
/* ----------------------------------------------------------------
*
* ----------------------------------------------------------------
*/
Datum
int4notin(PG_FUNCTION_ARGS)
{
int32 not_in_arg = PG_GETARG_INT32(0);
text *relation_and_attr = PG_GETARG_TEXT_P(1);
Relation relation_to_scan;
int32 integer_value;
HeapTuple current_tuple;
HeapScanDesc scan_descriptor;
bool isNull,
retval;
int attrid,
strlength;
char *relation,
*attribute;
char my_copy[NAMEDATALEN * 2 + 2];
Datum value;
/* make a null-terminated copy of text */
strlength = VARSIZE(relation_and_attr) - VARHDRSZ;
if (strlength >= sizeof(my_copy))
strlength = sizeof(my_copy)-1;
memcpy(my_copy, VARDATA(relation_and_attr), strlength);
my_copy[strlength] = '\0';
relation = (char *) strtok(my_copy, ".");
attribute = (char *) strtok(NULL, ".");
if (attribute == NULL)
elog(ERROR, "int4notin: must provide relationname.attributename");
/* Open the relation and get a relation descriptor */
relation_to_scan = heap_openr(relation, AccessShareLock);
/* Find the column to search */
attrid = my_varattno(relation_to_scan, attribute);
if (attrid < 0)
{
elog(ERROR, "int4notin: unknown attribute %s for relation %s",
attribute, relation);
}
scan_descriptor = heap_beginscan(relation_to_scan, false, SnapshotNow,
0, (ScanKey) NULL);
retval = true;
/* do a scan of the relation, and do the check */
while (HeapTupleIsValid(current_tuple = heap_getnext(scan_descriptor, 0)))
{
value = heap_getattr(current_tuple,
(AttrNumber) attrid,
RelationGetDescr(relation_to_scan),
&isNull);
if (isNull)
continue;
integer_value = DatumGetInt32(value);
if (not_in_arg == integer_value)
{
retval = false;
break; /* can stop scanning now */
}
}
/* close the relation */
heap_endscan(scan_descriptor);
heap_close(relation_to_scan, AccessShareLock);
PG_RETURN_BOOL(retval);
}
Datum
oidnotin(PG_FUNCTION_ARGS)
{
Oid the_oid = PG_GETARG_OID(0);
#ifdef NOT_USED
text *relation_and_attr = PG_GETARG_TEXT_P(1);
#endif
if (the_oid == InvalidOid)
PG_RETURN_BOOL(false);
/* XXX assume oid maps to int4 */
return int4notin(fcinfo);
}
/*
* XXX
* If varattno (in parser/catalog_utils.h) ever is added to
* cinterface.a, this routine should go away
*/
static int
my_varattno(Relation rd, char *a)
{
int i;
for (i = 0; i < rd->rd_rel->relnatts; i++)
{
if (namestrcmp(&rd->rd_att->attrs[i]->attname, a) == 0)
return i + 1;
}
return -1;
}